The Broncos didn't activate Boone (quadriceps) from injured reserve Saturday, making him ineligible to play Sunday against the Steelers, Nick Kosmider of The Athletic reports.
Head coach Vic Fangio teased a potential Boone return Sunday while the running back practiced for a second straight week, but the Broncos will ultimately keep him off the 53-man roster for a little longer. Since Boone's 21-day evaluation window opened Sept. 29, Denver will have to activate him by Oct. 20, or shut him down for the season. While Boone is idle for at least one more game, Damarea Crockett will serve as the No. 3 back behind Melvin Gordon and Javonte Williams.